Abstract: A spool valve comprising a body portion with a general center bore, three annular chambers and a seal land between adjacent chambers, a spool portion slidably disposed in the bore and having two semicircular circumferential grooves to form a spool land associated with each of the chambers, the spool lands and seal lands being so disposed that when the spool is in a first position the annular chamber on one end is in fluid communication with the center chamber and the spool land associated with the one end chamber and the spool land associated with the center chamber are equidistant from the adjacent seal land and the other seal land and the spool land associated with the chamber on the other end cooperates with the other seal land to form a seal between the center chamber and the other end chamber and when in a second position the annular chamber on other end is in fluid communication with the center chamber and the spool land associated with the other end chamber and the spool land associated with the center

Abstract: The present invention is an apparatus 10 for hydraulically slowing a member (12), preferably an engine poppet valve, to an acceptable impact seating velocity as the valve (12) is moved from open to closed. The poppet valve (12) has a stem (16) having a first portion (18) connected through a stepped portion (20) to a second portion (22) having a greater cross-sectional area than the first portion (18). The valve (12) rides within a guide body (28) having an opening (34) in an end wall (32) thereof through which the first portion (18) of the stem (16) extends. A hydraulic fluid space (50) is formed by the guide body (28) and the valve (12). As the valve (12) closes, fluid is forced out of the space (50) through a first fluid exit opening (66). As the valve (12) nears its seat (44), the fluid still in the space (50) is forced out through a second fluid exit opening (68) through which the rate of flow is less than the rate of flow through the first fluid exit opening (66).

Abstract: The invention described herein is a system (5) and method for opening an engine valve (12) by hydraulic force and for slowing the engine valve (12) by hydraulic force to an acceptable impact velocity when the engine valve (12) closes. Basically, a snubbing valve (10) is situated between the rail (40) that transports the high pressure hydraulic fluid needed to open the engine valve (12) and the engine valve (12). The snubbing valve (10) allows relatively unrestricted flow of the fluid in the direction from the rail (40) to the engine valve (12) so that adequate high pressure fluid can be provided to quickly open the engine valve (12). When the engine valve (12) returns towards the closed position under the force of a return spring (72) the snubbing valve (10) then restricts the flow of fluid out of the cavity (52) between the snubbing valve (10) and the engine valve (12) so as to slow the engine valve (12) to an acceptable impact velocity.

Abstract: An apparatus adjustably controls intake and exhaust valve movement and fuel injection of an engine. Valve movement and injection is adjustably controlled in response to electrical signals delivered to a piezoelectric motor which in turn delivers hydraulic signals through a single spool valve.

Abstract: A system in which movement of a first member from a first position to a second position is translated through fluid in a fluid chamber to movement of a second member from a first position to a second position, the system having a pressure equalization line in communication with the fluid chamber allowing fluid to flow into the chamber when the second member is at its first position and out of the chamber when the second member nears the first position when returning from its second position towards its first position.

Abstract: An apparatus adjustably controls intake and exhaust valve movement and fuel injection of an engine. Valve movement and injection is adjustably controlled in response to electrical signals delivered to a piezoelectric motor which in turn delivers hydraulic signals through a single spool valve.